http://www.lydsy.com/JudgeOnline/problem.php?id=1588 直接set做就好了,注意set的迭代器只能--之类的操作. OJ崩了,也不知道对错. #include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #include<set> using namespace std; set<int> s; se…